Prison-cell-door mechanism.



D. B. VAN DORN & J. T. WHITEHOUSE.

PRISON CELL DOOR MECHANISM.

APPLICATION FILED JUNE 6, 19 10.

Patented Oct. 31, 1911.

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D. B. VAN DORN' & J. T. WHITEHOUSB.

PRISON CELL DOOR MECHANISM.

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D. B. VAN' DORN & J.-T. WHITEHOUSE.

PRISON CELL DOOR MECHANISM.

APPLICATION FILED JUNE 6, 1910.

- Patented Oct. 31, 1911.

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PRISON CELL DOQR MECHANISM.

AIPLIGATION FILED JUNE 6, 1910.

Patented 01111. 31,1911.

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PRISON CELL DOOR MECHANISM.

APPLICATION FILED JUNE 6, 1910.

Patented Oct. 31, 1911.

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D. B. VAN DORN & J. T. WHITEHOUSE.

PRISON CELL DOOR MECHANISM.

APYLIOATION FILED JUNE 6, 1910.

Patented Oct. 31, 1911.

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D. B. VAN DORN & J. T. WHITEHOUSE.

PRISON CELL DOOR MECHANISM.

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Patented Oct. 31, 1911.

APPLICATION FILED JUNE. 6, 1910.

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D.-B. VAN DORN & J. T. WHITEHOUSE.

PRISON CELL DOOR MECHANISM.

APPLICATION FILED JUNE 6, 19 10. 1 6 Patented Oct. 31, 1911.

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UNITE STATES PATENT OFFIC,

DWIGHT B. VAN DOB-N AND JOHN T. WHITEHOUSE, OF CLEVELAND, OHIO,ASSIG-NORS TO THE VAN DORN IRON WORKS COMPANY, OF CLEVELAND, OHIO, ACORPORATION OF OHIO.

PRISON-CELL-DOOR MECHANISM.

T 0 all whom it may concern:

Be it known that we, DWIGHT B. VAN Donn and JOHN T. WVHITm-IoUsE,citizens of the United States, and residents of Cleveland, .in thecounty of Cuyahoga and State of Ohio, have invented a certain new anduseful Improvement in Prison-Cell-Door Mechanism, of which the followingis a full, clear, and exact description.

This invention relates to locking mechanism for prison-cell doors inwhich key locks on the cell doors are dispensed with and suitablemechanism provided for opening or closing and locking or unlocking anyor all of the doors of a. series of cells opening upon a commoncorridor, said mechanisms being adapted to be operated and controlledfrom a position outside of said corridor and closed off or otherwisemade inaccessible therefrom so that the operator may be kept fromintimate personal contact with the prisoners and safe from any suddenattack by them when released from their cells to the corridor. Itsprincipal objects are, first, to provide initial operative mechanismsmounted and inclosed in a suitable casing located outside of thecorridor upon which the cell doors open, which casing will forconvenience be hereinafter called the lock box; second, to extend fromthe mechanisms in this lock box suitable connections to the individuallocking and operating mechanisms at each of the several doors of such aseries, such connections being inclosed andguarded from access by alongitudinal steel casing extending the length of the corridor above allthe doors, which casing for convenience will hereinafter be called thebox casing; third, to provide and control from the lock box, certainsnaplock and dead-lock mechanisms at each individual cell door, whichmechanisms are partially inclosed in the box casing above referred tobut mainly in a steel pilaster or vertical casing standing at one sideof each door opening and at the outer end of each partition wall betweentwo cells. This vertical casing connects at its upper end with the saidbox casing and will hereinafter be referred to as the jamb casing;fourth, to provide means whereby the snap-lock mechanism is held underrestraint in unlocked position while the door is open, but is tippedinto release by the closing door and snaps into locking engagement withthe Specification of Letters Patent.

Application filed June 6, 1910.

Patented Oct. 31, 1911.

Serial No. 565,214.

door; fifth, to provide means controlled from the lock-box whereby suchunlocked doors as are engaged by a longitudinally movable master bar maybe moved simultaneously to open or closed positions, or held in anydesired positions; sixth, to provide means whereby any unlocked door orselected plurality of unlocked doors may be released from said masterbar and left free to be moved by hand from the corridor or from theinterior of the cell to open them farther or to close and automaticallylock them; seventh, to provide means located in the lock box whereby theindividual lockcontrolling mechanisms for the doors may be operatedsimultaneously by a general actuating mechanism associated with them inthe lock box; eighth, to provide means located in the lock box wherebythe individual controlling mechanisms of any door, or selected series ofdoors may be removed from the influence of such general actuatingmechanism and the snap locks of such selected doors, dead-locked againstaction while their controlling mechanisms at the lock box remain in suchpositions; this removal of the controlling mechanisms of one or more ofthe doors from the path of the general actuating devices and thedead-locking of such doors in no way affecting the operation of theother doors while guarding against the accidental unlocking, etc., ofthe particular doors which it may be desired to leave closed andsecured.

The invention, embodied in the form now deemed most desirable, ishereinafter de scribed, specifically pointed out in the claims at theend of this specification and shown in the accompanying drawings inwhich:

Figure 1 is a front elevation of the corridor face of two cell doors ofa series, the

front cover plates being omitted from the vertical amb casing atthe leftside of each door opening and also fromthe overhead box casing whichextends the length of the corridor above all the doors; the verticaljamb casings containing the individual snap locking and dead-lockingmechanisms for their doors, and the overhead box casing the devices foroperating the doors and the transmission connections from the lock boxoutside of the corridor to the individual mechanisms at the cell doors.Fig. 2 is a horizontal section of the same in the plane of the line 2 2.of Fig. 1 and the line 1111 of Fig. 8. Fig. 3 is a front elevation ofthe lock box or casing located outside of the corridor and lnclosingportions of the selective, operating and controlling devices of thedoors and their locking mechanisms. Fig. l is an elevation partly insection on the lines 1 a of Figs. 3 and 7, of the lock box, togetherwith some adjacent portions of the first cell door of the series withportions of its individual locking and operating devices. Fig. 5 is afront elevation showing a portion of the selective operating mechanismlocated in the lock box, with the front of the box removed, and as seenfrom the direction of the arrows on the plane indicated by lines ofFigs. 4; and 6. Fig. (3 is a side elevation of the same partly insection on the lines 6'6 of Figs. 3, 5 and 7. Fig. 7 is a plan viewpartly in horizontal section on the plane of lines 77 of Figs. 3, 5 and6. Fig. 8 is a front elevation, partly in section on the lines 88 ofFigs. 2, 9, l0 and 11 of portions of the vertical jamb casing andoverhead box casing, as they join, at one side of each cell-dooropening. Figs. 9, 10 and 11 are horizontal sections on the planes of therespectively numbered section lines of Fig. 8. Fig. 12 is a rear orinside elevation, partly in section on the line 1.212 of Fig. 13, of aportion of the overhead box casing and a portion of the upper end of adoor projecting therein and supported thereby, with various details ofconstruction. Fig. 13 is a transverse sectional view of the same partson the line 1313 of Fig. 12. Fig. 14: is a detailed view of the sleevenut and grooved spindle, in transverse section on the line 14t1 l ofFig. 6. Fig. 15 is a perspective detail of a short section of thepilaster or jamb casing which incloses the snap lock devices of the celldoor. Fig. 16 is a sectional view of the same on the line 1616 of Figs.11 and 15. Fig. 17 is a diagrammatic perspective view showing a singletrain of the principal elements necessary to carry out the operation ofthe mechanism for a single door. This figure is made for descriptivepurposes chiefly, and without special regard for pro portions or theexact relative planes or positions of the parts. Figs. 18 to 22,inclusive, are diagrammatic views showing the relative positions ofparts of the snap lock and dead-lock mechanisms and also of the boltconnecting the door to the master bar, at several stages of locking, andunlocking the door, the actual relative positions and planes ofcooperating parts being ignored to some extent for purposes of clearerillustration.

The invention is illustrated in its application to a series of cellsseparated by me tallicplate partitions o and opening upon a commoncorridor, their corridor ends be ing closed at one side by a fixedgrating A which leaves an opening at the other side to be closed by asliding grilled door A, carried by a hanger a, provided with rollers at,on a track rail Z), in the overhead box casing B. See Figs. 1, 4, 12 and13. At the side of the door opening, opposite the fixed grating, is avertical pilaster or jamb casing C which preferably stands in front ofand is connected to the steel plate partition between two cells, (Fig.and it contains the locking devices for its particular door. These jambcasings extend from the floor to and are connected with the box casing Bwhich extends along the corridor above all the doors and connects withthe lock box D located in an ante-room outside of the corridor. Theoverhead box casing 13 contains parts, of the individual doorlocking anddoor-moving mechanisms and also the transmission rods, etc., extendingfrom the lock box D in the ante-room to the several doors along theseries. The side plates 0 of the jamb casing extend upwardly through thebox casing forming partitions therein which are suitably apertured forthe passage of the several longitudinal elements and members of thelooking devices which cross its plane.

Each door A comprises a rectangular frame of flat bars on its outer sideand bottom end, with a vertical angle bar (1 on its front side and avertical hanger plate a at its top which is flanged inwardly at itslower edge, the space thus inclosed being grilled by suitable verticalbars and cross braces as shown. The angle bar a is disposed with theflat face of its longest leg outwardly and parallel with the plane ofthe door. It is adapted to pass into a vertical slot 0 of the jambcasing C and is apertured at a to be engaged by a snap bolt in saidcasing. The hanger plate (4 extends upwardly through a narrow slot Z) inthe bottom of the box casing B within which it supports the guiderollers a as stated. See Fig. 13.

A connecting bolt E vertically movable in bearing lugs on a guidebracket E adjustably mounted on a base frame E rigidly secured to theinner face of the hanger plate a, is adapted to engage a notch f in alongitudinally movable master bar F in the box casing and therebyconnect the door to said master bar. The notch f in the master bar isformed in a plate f having inclined sides f at each side of the notchand is rigidly secured to the bar. In order to adjust the doorrelatively to the notch in the master bar and thereby admit of each doorbeing brought to its exact locking position, the guide bracket E whichcarries the bolt is so pivoted at e on the base frame to swing sidewiseat its lower end, which end is held by a clamping bolt 6' moving in aslot 6 in the base and by set screws 6 passing through lugs e risingfrom the base plate; see Figs. 12 and 13. The bolt is vertically movableon the guide bracket and carries a roller 6 on its inner face which isengaged by an underlying, movable lift rail G carried by rollers g andheld in position by guard bars 17 supported upon the inner wall of thebox casing. The lift rail is widened at each end and has shallowV-shaped notches g in its lower edge to receive the supporting rollersg. This lift rail is movable endwise and when so moved, by meanscontrolled at the *lock box D, the inclined sides of its notches g"resting on the rollers g raises or lLHVQI'n' the rail bodily as the casemay be.

Vitliin the pilaster or amb casing is the snap-lock device for the doorcomprising a vertical shaft H rotatable in suitable bearings in thecasing and provided near its lower end with a lever arm H engaging anotch h in a horizontally movable lock bolt H mounted in a housing 71rigidly secured to the inner walls of the casing. A socket 71 contains astrong spiral spring 72. which bears against the lever arm H and tendsto rotate the shaft in a direction that will move the bolt H to lockingposition. See Figs. 8, 11 and 17, in which, however, the bolt is shownin retracted position. The rear wall of the notch 71, in the bolt is ofan exact height to free the lever arm H and allow it to pass out of thenotch when the bolt is fully retracted whereby the shaft is freed forfurther rotation in this direction. When the lever arm leaves the notchthe bolt is held against accidental movement toward locking position byits curved face 71. standing in opposition to the end of the lever H.hen the shaft H is turned against the stress of the spring k to unlockthe bolt it is caught and held in unlocked position by a dog H engaginga holding cam H secured on the upper end of the shaft. The dog ispivoted at if under the top plate of the box casing and is pressed intoengagement with the cam by a spring h" and is carried by a guard plateif which has an extension 7L8 underlying and supporting the free end ofthe dog, which end extends beyond the cam and is notched to suitablyengage it as shown in Figs. 9 and 17. At the top of the hanger plate aof the door is secured a bracket 1 provided with a trip finger 2'adapted, when the door is nearly closed, to extend through an opening 0near the top of the partition plate 0 (see Figs. 1, 8, 9 and 13) andcontacting with the dog H and push it out of engagement with the holdingcam H thus releasing the shaft and allowing the lever arm H to throw thelock bolt H into loching position across the slot 0 of the iamb casingand through the aperture 64 of the door angle which enters the slot asthe door closes. The bracket I also carries a buffer rod 2" actuated bya spring 2' to project its end in advance of the door frame. WVhen thedoor is being closed this rod engages a suitable fixed obstruction, inthis case the partition wall 0, which halts the rod and compresses itsspring during the short continued movement of final closing of the door,thereby storing power in the spring which, when the door is nextunlocked and released, will push and give the door an initial openingmovement of several inches, serving to carry its front angle bar out ofthe slot 0 in the jamb casing and entirely out of range of the lockingdevices, and it also serves to retract the tripping finger z, leaving acleared space'for the dog H to engage the holding cam H when thesnaplock mechanism is reset. The shaft H is turned to the unlockingposition by means of a lever H secured to the shaft and hav ing its freeend standing in the path of a projecting lug j on an endwise reciprocalrack bar J controlled from the lock box in the anteroom. In the normalposition of the parts, or when the snap lock is in looking engagementwith the door, this lever H stands in such relation to the lug 9', shownby dotted lines in Fig. 10, and by full lines in Figs. 18, 19 and 22,that when the rack bar J has made a certain amount of preliminarymovement in its operation to unlock the door, etc., it will encounterthis lever and by continued movement swing it and rock the shaft H,thereby moving the snap lock back and the holding cam H into engagementwith the dog H. The return movement of the rack bar leaves the shaft Hand its several parts as just described, this movement of the rack barmerely serving to set the shaft and the snap lock in unlocked, caughtposition.

Associated with the snap lock is a deadlocking device comprising aheavy, vertically movable bar J, supported in guides against the rearwall of the jamb casing in the path of the lock bolt H and having asolid dead-block 7" attached at that portion of it near the lock bolt.When the lock bolt is unlocked this dead block stands above its back endbut when the lock bolt is shot the dead block drops behind it forming asolid backing to prevent retraction of the bolt while the dead block isin this position. The dead lock bar J extends up through the jamb casingand into the box casing where its width is reduced and a gear rack 7'formed on its edge. This rack engages a gear wheel J which is mounted ona fixed bearing 7' and is also engaged by the rack bar J before referredto. This rack bar is connected at one end by the rod to the lift rail Gbefore referred to, and at the other has a rod connection K leading tothe controlling mechanism in the anteroom. Vhen the rack bar J is movedin the direction of the full line arrows on Figs. 1, 8 and 17, to unlockthe door, it draws the lift rail G to raise the door bolt. E out ofengaging range of the notch f of the master bar F and at the same time,through the gear wheel J raises the lug j of the dead-lock bar J frombehind the lock bolt H In its continued movement the rack bar lug jencounters the lever H at the position shown by dotted lines, Fig. 10,and moves it to position shown by full lines, which movement rotates theshaft H, and effects the complete retraction of the lock bolt H andengagement ot the dog H with holding cam H The connecting rod K,extending toward the mite-room, is subjected to tension strains inpulling the previously described parts into unlocked positions and theweight of the dead-lock bar J acts as a counter force to restore theparts when the tension on rod K is slackened.

The master bar F lies close to the bottom of the box casing, extendsover every door in the series and above each door is provided with anotched plate f adapted to engage the connectin bolts E at the top ofthe door. These bolts, as before stated, may be raised above the planeof the notches f by the lift bars G and thus held out of engagcnientwith the notches f as the master bar is reciprocated. If, however, thebolt E is lowered to the plane of engagement it will be lifted by anincline f of the plate 7'' and drop into the notch f and thus connectthe door to the master bar so that it will be moved to open or closedpositions thereby. This master bar is independently movable and may bedead locked at either extreme of its throw. it is operated by a lever Fonthe lock box D. This lever half turns a gear wheel a engaging gearteeth f on a vertically movable rack bar F provided at its upper endwith another set of gear teeth f engaging a gear wheel F mounted on ashaft f supported in suitable bearings and provided with a crank arm Fto which is pivotally connected a link bar F extending from the anteroominto the end of box casing B, where, through suitable connections, itoperates the master bar, see Figs. 3, dr, 7. A pair of spring clampingdevices a? and a? extend from the wall of the casing (as shown in Fig.and yieldingly hold the lever in either of its two positions way up orway down. In order to eccnr mize space these connections are of such anature as to move the master bar twice as far as the half turn throw ofthe crank F. To accomplish this the link F is connected to the shaftjournals 7" of a reciprocal gear wheel F which engages at its top withthe teeth of a fixed gear rack F and on its lower side with a gear rackF rigidly secured to the end of the master bar, see Figs. land 17. Inthis arrangement the upper side of the gear wheel F being held by itsengagement with the fixed rack F its peripheral movement at this pointof contact is zero relatively to the longitudinal movement of the shaftf while its lower side moves in the same direction as the shaft buttwice as fast, therefore imparting to the ack F a longitudinal movementtwice as great that of the shaft f. The gear rack bar F is secured toand longitudinally adjustablc on a bracket F rigidly fastened to theinner wall. of the box casing. Bolts pass through slot f in. the bracketF and are screwed into the rack bar while set screws F pass through lugson the ends of the bracket and bear upon the ends of the rack bar. Thisadjustnientof the rack bar acts, through the gear wheels to move themasterbar and adjust its relation to the throw of the crank F The meansfor controlling the several described agencies at each door, through thetension rods K, are located in the lock box D in the anteroom, each doormechanism having its individual rod K connecting with its individualcontrolling mechanism at said lock box. In the organization of thiscontrolling mechanism simplicity of construction and operation,efliciency and certainty in action, lessened liability of mistakes, andeconomy of room are prime considerations.

At the anteroom end of the rod K it is connected to a gear rack inendwise reciprocal in suitable guides and engaged by a gear wheel Kmounted on a vertical bearing shaft Another gear rack K disposed at aright angle to the rack 71 and endwise reciprocal in suitable guides isprovided on one side with a set of gear teeth 70 which engage the gearwheel K and on the other side, at a proper distance from the first, withanother set of gear teeth 70* which engage a gear wheel L on the upperend of a vertical rotatable spindle L mounted in suitable guides in thelock box. Deep spiral grooves Z cut in the spindle are engaged bysuitable lugs or lands a in the bore of a long sleeve nut N (see Fig.14) which is rigidly secured to the upper end of a vertically movablebar 0 mounted in suitable supports 0, 0 in the lock box D. The sleevenut N is provided with a side lug n on which is mounted a roller n whichtakes into a guide slot 39 in a plate P extending across the lock box Dnear its front face, which roller reciprocates in the slot and preventsthe sleeve and attached bar 0 from turning. The sleeve is recessed at na suitable distance below the end of the grooved spindle to permit it torise on the spindle above the position shown in the drawings. On thesleeve is a rearwardly projecting foot n and a rearwardly projecting lugn for purposes to be presently explained. The bar O between its bearingsupports 0 and 0 is provided with a collar Q which limits its upwardmovement by contact with support 0 and it is also provided with a strongspiral spring Q having suflicient expansive force to easily raise thebar, collar, etc. While it is convenient in this embodiment of theinvention to use springs to raise these bars, it will be understood thatcounterweights or other suitable means for obtaining yielding force maybe employed in their stead for this purpose, and the term springpressure used herein is intended to cover any such means. Above the barguide 0 is a movable locking slide R adapted to engage and hold the bardown to its normal semi depressed position as shown in the drawings.This locking slide is mounted in a suitable bracket, (see Figs. at and6) secured to the bar guide 0 and having two upward extensions 1' and 1*which support and guide the slide member. Two studs r and r project fromthe rear extension 1' and engage apertures in the slide member, theupper one of which forms a deep socket for the reception of a spring rlying between the bottom of the socket and the end of the stud to pressthe slide forward. The front extension of the bracket is apertured forthe passage of the locking toe r of the slide and also for the passageof a push rod T which projects through the front (Z of the lock box andcarries a finger piece or button R. The bar 0 is preferably slotted asat- 0 for the reception of the *toe of the slide and the passage throughit of the push finger rod 1*.

A lever S is pivoted at s in the lock box and projects out of the frontof the box through a slot 8 and also preferably passes through a slot 0in the bar 0. It is connected by a link T to the lug n on the sleevenut.

A depressor lever U pivoted at u, extends across the lock box in rear ofthe sleeve nuts and has links V pivotally connected to it at u, saidlinks being pivotally connected at their lower ends to pivots w on leverarms V secured on a rock shaft V which extends across the look box. Thisshaft is supported in suitable bearings 'w, to in the lock box andprojects out of it at the left side, Fig. 3, where it is provided withan operating lever X. A spring clamping device m (Figs. 3 and 4:)extends from the rear wall of the lock box and holds the lever X in itsnormal raised position of rest. When these several parts are in theirnormal positions, which they occupy when the cell doors are closed andnormally locked, the depressor bar U, when rocked toward the sleeve nutN will engage the top of the projecting foot n on the upper end of thesleeve and in its continued movement will bear down upon and depress thesleeve N and bar 0 to a lower position against the stress of the liftingspring Q at the lower end of said bar for a purpose to be explainedlater. The

master bar F and this depressor lever U are =both common to all of thedoor mechanisms, but all of the other parts heretofore described relateto a single system or train of mechanism for a single door, which systemis duplicated for every door inthe series. The rack bars are arranged invertical order in their guide block as shown in Figs. 3, 4, 5, 6 and 7,the corner gear wheels K are stacked upon the common bearing pin 70 Therack bars K are disposed in vertical series in proper guides and theirgear racks 70 engaging the wheels K are all alike, but the bars areprogressively lengthened as they rise in the series, and their gearracks lo are correspondingly and successively farther removed from theracks 70 to adapt them to the positions of the gear wheels L on thegrooved spindles L. These spindles are successively lengthened fromright to left in the series to support their wheels L in thesuccessively higher planes of their respective rack bars 70* in theseries.

In the operation of the devices the several mechanisms immediatelyassociated with each door, to lock or unlock and release it, areoperated through the draw rods K, the movements of which are controlledby the sleeve nuts N which rotate the spindles L. lVhen the sleeve nutis raised the spindle-is rotated in the direction of the dotted arrowtherein (Fig. 17) and obviously in the reverse direction of the fullline arrow when the sleeve nut is depressed, the resulting movement-s ofthe several mem bers afiected thereby being shown by correspondingdotted and full line arrows. Now, when the door is closed and normallylocked, or when it stands open with. its snap lock set and ready toengage the closing'door, those parts of the controlling devices shown atthe left of Fig. 17 (supposed to be inclosed by the lock box D) are,generally, in the positions shown in said figure. The individualdepressing levers S of which there is one for each door in the series,project out through slots 8 in the front face of the lock box, the slotsor levers being suitably marked to indicate the respective doors towhich they belong. The levers S may be moved to any one of threepositions which are indicated by lines on the front face of the lock boxand preferably marked Deadlocked Locked and Unlocked respectively. Thesepositions of the levers indicate the state or condition of theirrespective cooperating mechanisms. The sleeve nuts and their bars areall raised, when permitted, by their lifting springs Q and they may belowered, individually, through their levers S, or in multiple by thegeneral depressor lever U engaging all of the projecting feet 11/ of thesleeves which stand in its path. The pull on the rod K, caused when thesleeve is being depressed below its nor mal position, effects theraising of the deadlock block j from behind the snap lock bolt H andalso the raising of the door-connecting bolt E above the plane ofengagement with the notch f of the master bar F. The next effect is tocarry the lug on the rack bar J into contact with the lever H and drawback the snap lock, releasing the door and permitting it to be pushedopen by the spring plunger 2" a sufficient distance to carry its tripfinger 2' out of the way of the dog H and admit of its engagement withthe holding cam H to hold the snap lock in reset position. The sleevenut, after its depression to unlock the door, is immediately raised bythe lever S or by the spring Q to its normal position, thereby loweringthe door-connecting bolt E so that it may be engaged by the notch f ofthe master bar and the door moved or held in control thereby. All of theforegoing operations are those pertaining to normal locking only, asdistinguished from the dead locking of any selected door or number ofdoors of the series.

To effect dead-locking the sleeve nut must be raised above its normalposition to that shown in dotted lines in Fig. 6, in which position itsprojecting foot 12 will be raised above and out of the path of thegeneral depressor lever U, so that it cannot be borne down when saidlever is swung to depress other sleeve nuts of the series. The sleevenut and its attached bar are held in normal position, against the upliftof the spring Q by the spring-pressed locking slide R engaging the slot0 in the bar 0. The push rod 1" with its finger button R enables theoperator to move the locking slide back out of this engagement andpermit the bar and sleeve nut to rise to the dead-looking position(shown by dotted lines) where they will be held by the uplift of thespring Q until brought down by the lever S and again engaged by thelocking slide. The raising of a sleeve nut above its normal position, asjust described, not only removes it from the field of action of thegeneral depressor lever U, but also, through turning the grooved spindleL, in the direction of the dotted arrow, slackens the tension on the rodK and permits the dead-lock lug j to drop still lower than normal,behind the snap-lock bolt H It also has the effect of moving the liftrail G to the right and raising it sufficiently to raise thedoor-connecting bolt E above the plane of engagement with the notch f onthe master bar. Briefly, this upward movement of the sleeve nut isolatesit from the general depressor lever U and prevents connection of itsdoor with the master bolt, so that the depressor lever and the masterbar may be freely used in operating all other doors not so connected.

Figs. 18 to 22, inclusive show various phases of the relative positionsof the parts of door-locking and operating mechanisms at several stagesof unlocking the snaplock, releasing the door therefrom and engaging itto the master bar. In Fig. 18 the parts are shown in positions assumedwhen the door is closed and normally locked. The snap-bolt H engages theaperture a of the door angle (6 the lug j stands partially behind thesnap-bolt, semi dead-locking it; the lift rail G is resting upon therollers g at the lowest point of its edge, thereby rais ing it to aplane high enough to raise the door-connecting bolt E above the plane ofengagement with the notch f of the master bar F. A part of thedoor-hanger plate a upon which the bolt E is slidably mounted is shown,said plate moving with the door and the roller a riding along upon thelift rail G. Fig. 19 shows the start to unlock the door. The sleeve nut(not shown in these figures) is lowered, and the draft upon the rod Kmoves the parts operated by it to the positions shown in this figure, inwhich the dead-lock lug j is raised above the plane of the top of thesnap bolt H leaving free passage for the retraction of said bolt; thelug j on the rack bar J engages the lever H and the lift rail is drawnto a position where the rollers g stand in the deepest part of the railnotches 9 Fig. 20 illustrates the effect of continued pull on the rod K.The rack J is moved to the end of its throw and its lug j rocks thelever H to the position shown in this figure, which rocking movement,through the shaft H, etc, causes the retraction of the snap bolt H Thedead lock lug j is raised clear above the snap bolt H and the lift rail,riding up on the rollers g at the far side of its notches, has liftedthe door bolt E above the plane of the notches of the master bar. Duringthese movements the door, when released from the snap bolt, is sprungback and opened a few inches by the spring plunger 2" before mentioned.Fig. 21 shows the completion of the unlocking movements. lVhen thesleeve nut is raised, immediately following its depression to unlock,the rod K is slackened and all of these immediately associated parts atthe deer are partially retracted by the weight and fall of the dead lockbar J which drops until its lug j is checked by and rests upon the topof the snap bolt H This initial. movement of the dead-lock bar draws allof the other parts to the positions shown in this figure. This initialmovement of the dead-lock bar is through a small part only of itstraverse in this direction, and it takes up only half of the slack inthe connection K. The snap bolt is retracted and the door freed from itsrestraint, the lift rail rests with the deepest parts of its notches onthe rollers g and the door-connecting bolt lowered to the plane ofengagement with the notch f of the master bar. If not already inengaging position when the bolt E is lowered, the master bar may bemoved endwise until the bolt drops into the notch, the bolt riding upone of the inclines f at either side of the notch. lVhen thus connectedto the master bar the door is positively controlled by it and may not bemoved independently of it. If desired, however, the door may bedisconnected from the master bar through a pull on the rod K from thelock box, raising the lift rail and door bolt while the masterbar notchis moved away from beneath the bolt. Fig. 22 illustrates the dead-lockedposition of these parts resulting from the lifting of the sleeve nut Nabove its normal position and out of the range of the general depressinglever U, as shown by dotted lines in Figs. 6 and 17, and therebythrowing additional slack into the rod K. It will be understood thatthis deadlocking preferably, though not necessarily, follows thenormally locked position shown in Fig. 18, where the dead-lock lug j isalready behind the snap bolt. Now this additional slacking ofi of therod K permits the dead-lock lug j to sink still lower behind the snapbolt and this movement causes the lift rail G to move along to the rightwith its parallel surfaces g resting upon the rollers g retaining therail at its high level and holding the door bolt E above the plane ofengagement with the notches f of the master bar.

While the dead-lock bar is preferably made heavy enough to serve as aweight in drawing back the slack in the connecting rod K and to move itsassociated parts at the door, as described, it might be preferred toemploy a separate weight or other suitable means to retract theconnection K and perform the offices of the weight subject to thecontrol of the dead-lock bar.

Having described our invention, we claim:

1. In a prison cell door, the combination of a vertical amb casing atthe closing side of the door opening and slot-ted along its entirelength on the door side thereof, looking mechanism in the casing, with aslidable door having at its closing side a vertical plate extendingsubstantially its entire length projecting beyond the edge of the doorproper and adapted to pass into the said slot of the casing and there beautomatically engaged by said locking mechanism.

2. In a prison-cell door, the combination of a vertical jamb casing atthe closing side of the door opening and slotted lengthwise on the doorside thereof, spring locking mechanism with means for restraining it inunlocked position, a slidable door having at its closing side a verticalplate project ing beyond the door proper and adapted to pass into saidslot of the casing there to be engaged by said locking mechanism, withmeans carried by the door adapted to trip and release the said lockingmechanism after said plate has entered the slot in the casing.

3. In a prison-cell door, the combination of a slidable door, anautomatic locking mechanism adapted to engage and lock the door whenclosed, means for retracting said mechanism to unlocked position, meansfor holding said mechanism in restraint in its unlocked position, meanscarried by the door whereby in closing it trips said restrainingmechanism and thereby releases the locking mechanism, with means adaptedto automatically push open the unlocked and released door sufficientlyto remove the said tripping device from the path of the lock-restrainingmeans.

4. In a prison-cell door, the combination of a jamb casfiig having avertical slot on the door side thereof, a slidable door having anapertured flange plate adapted to pass into said slot, a spring actuatedbolt in the casing movable transversely across the path of said flangeplate and adapted to engage the aperture therein, means for retractingsaid bolt, and means for holding it in retracted position, with meanscarried by the door adapted to trip said holding means and release thebolt, allowing it to move into locking position, and a spring plunger onthe door adapted to engage a fixture and compress its spring on thefinal closing movement of the door to impart an initial opening movementto the door when it is unlocked.

5. In a prison-cell door, the combination of a jamb casing having avertical slot on the door side thereof, a slidable door having anapertured flange plate adapted to pass into said slot in the casing, abolt in said casing movable transversely across the path of said flangeplate and adapted to engage the aperture therein, a vertical rock shaftin said casing, a lever on said shaft engaging the bolt, a spring urgingthe bolt to its locked position, means for rocking the shaft to retractthe bolt against the pressure of said spring to unlocked position, a camon the shaft, a pivoted spring-pressed dog adapted to engage said cam inits unlocked position, and a member on the door adapted to engage andtrip said dog on the final closing movement of the door.

6. In a prison-cell door having a jamb casing with a vertical slot onits door side and a slidable door having an apertured flange plateadapted to pass into said slot, the combination of a spring pressed boltin said casing adapted to engage the aperture in said door plate, amovable bar having a dead-lock block to lie behind the spring bolt whenthe latter is in locked position, with means for moving the dead lockout of the path of the spring lock, and means for retracting the boltafter the dead lock is so moved.

7. In a prison-cell door having a jamb casing with a vertical slot onits door side,

and a slidable door having an apertured flange plate adapted to passinto said slot in the casing, the combination of a bolt in said casingadapted to engage the aperture in the flange plate of the door, avertical rock shaft having a lever engaging said bolt, a spring pressingsaid lever and bolt to locking position, a second lever on the rockshaft, a vertically movable bar having a dead-lock block to lie behindthe bolt, a geared rack on said bar, a pinion engaging said rack, ahorizontal rack bar also engaged by the pinion and having a projectionadapted to engage said second lever on the rock shaft, with means forlongitudinally moving the horizontal rack bar whereby the dead lock isfirst raised and then the shaft rocked to retract the bolt.

8. In a prison-cell door having a suitable jamb casing, the combinationof a horizontally movable spring-lo king bolt in said casing, a verticalrock shaft operatively connected to said bolt, a lever on said shaft, avertically movable dead-lock bar lying behind said bolt and providedwith a gear rack, a pinion engaging said rack, a horizontally movablerack bar also engaged by said pinion, means for moving said rack bar aprescribed distance, and a projection on said rack bar adapted to en agethe free end of the said lever on the rock shaft, said projection beingso relatively disposed as to contact with said lever toward the latterpart of its prescribed movement.

9. In prison-cell door mechanism having a slidable door and a movablemaster bar, the combination of a connecting bolt mounted upon andmovable with the door and adapted to engage the master bar, with meansfor controlling the position of said bolt relatively to the master barat any point within the range of movement of the door.

10. In prison-cell door mechanism having aslidable door and a movablemaster bar, the combination of a connecting bolt mounted upon andmovable with the door and adapted to engage the master bar, with meansfor controlling the position of said bolt relatively to the master barat any point within the range of movement of the door, and holding thebolt in desired relation to the master bar during any of its movementswith the door by which it is carried.

11. In prison-cell doors, the combination of a series of cells havingslidable doors in their openings, a master bar longitudinally movable inthe same direction as the doors to all of which it extends, a notch inthe master bar for each door, a bolt in each door adapted to engage itsnotch in the master bar, with means whereby the position of the bolt onthe door may be adjusted in directions parallel with the movement of themaster bar.

12. In prison-cell doors, the combination of a series of cells havingslidable doors in their openings, a master bar longitudinally movable inthe same directions as the doors to all of which it extends, a notch inthe master bar for each door, with a slidable bolt on each door adaptedto engage its notch in the master bar, a housing for said bolt securedupon the door in such manner will admit of its adjustment in directionsparallel with the master bar, means for clamping it against the door,and rigid lugs on the door having set screws which bear against thesides of the housing substantially as and for the purpose hereinbeforedescribed.

13. In a. prison-cell door, the combination of a slidable door, a boxcasing located above the door and slotted on its lower side, a verticalplate at the top of the door extending through said slot, a verticallymovable bolt mounted on said plate, a longitudinally movable bar belowsaid bolt and having a notch adapted to be engaged by said bolt, withmeans for controlling the vertical position of the bolt relatively tothe plane of said notch.

14:. In a prisoncell door, the combination of a slidable door, a boxcasing located above the door and slotted along its lower side, a plateat the top of the door extending through said slot, a bolt verticallymovable in suitable guides on said plate, a longitudinally movablemaster bar below said bolt and having a notch adapted to be engagedthereby, with a movable lift rail supported on the casing and adapted toslidably support the bolt, and means for adjusting and maintaining theelevation of said lift rail as desired.

15. In a prison-cell door, the combination of a slidable door, a boltvertically movable in suitable guides secured to the top of the door, alongitudinally movable master bar below said bolt and having a notchadapted to be engaged thereby, with a movable lift rail adapted toslidably support said bolt, said lift rail having notches with. inclinedsides on its lower edge, rollers mounted on fixed bearing pinssupporting the lift rail on its lower edge, with means for moving thelift rail endwise on said rollers whereby its elevation is determined bythe relative positions of said notches and rollers.

16. In a series of prison cells with doors opening upon a commoncorridor, the combination of a vertically movable connecting bolt oneach door, an individual vertically adjustable lift rail at each door toslidably support said connecting bolt, and means for adjusting said liftrail, with a longitudinally movable master bar extending to all of saiddoors and having a notch with an incline at each side thereof for eachdoor adapted to be engaged by said connecting bolts, with means formoving said master bar to open or close the doors connected therewith.

17. In a prison-cell door, the combination of a jamb casing, aspring-lock bolt in said casing, at slidable door adapted to' be engagedby said spring-lock bolt, a vertically movable bar adapted to dead lockthe spring-lock bolt, a longitudinal'ly-m'ovable bar a dapted throughsuitable connections toraise the dead lock and retract the lock bolt tounlocked position, a vertically-movable connecting bolt supported at thetop of the door, a longitudinally movable master bar below said bolthaving a notch adapted to be engaged thereby, a'movable lift railadapted to slidably support said connecting bolt in its relation to saidnotch, and means whereby the endwise movement of said lift rail adjustsits elevation, said lift rail being connected to said first mentionedlongitudinally movable bar whereby the lift rail is moved simultaneouslywith the locking and dead-locking mechanisms to set the connecting boltin suitable relation to the mas ter bar.

18. Ina prison-cell door provided with suitable locking, dead-lockingand door-mov ing devices, the combination of a horizontally movablegear-rack bar suitably connected with and adapted tocontrol all of saiddevices, a pinion engaged by said gear-rack, a vertically movabledead-lock bar, a gear rack on said bar also engaging said pinion, withtension means for moving said first mentioned g'eara'ack bar inopposition to the weight of the dead-locking bar which weight serves toretract said gear-rack bar and its associated mechanisms-when relievedfrom said tension restraint.

19; In a series of prison cells, the combination at eachcell-dooropening of a slidable door, a horizontally-movable locking bolt adaptedto engage the door, a vertically movable bar adapt-ed to'dead-lock saidlocking bolt and in turn be checked in its descent by said locking bolt,a longitudinally movable master bar having: a notch at each door, amovable connecting bolt on the door adapted toengage anotch of themaster bar, means for controlling the position of said connecting boltrelatively to the plane of its engagement with said master bar notch,said means being controlled by and moving in unison with: the dead -lockbar, whereby when. the door is unlocked: the dead lock is first raised,then the locking bolt retracted across the path of the dead lockand'theconnecting bolt moved out of the plane of the master bar notch, then thedead-lock bar is lowered until it is checked by and rests upon the rearend of the retracted locking bolt and the connecting bolt on the doorbrought to and held in engaging position for the master-bar notch.

20. In a prison cell-door locking and operating mechanism having at thecell a slidable door and a longitudinallv movable master bar, thecombination of mechanism at the cell door comprising a connecting bolton the door adapted to engage the master bar, and means controlled bythe dead-lock bar for controlling its position, a snap-locking boltadapted to engage the door, a dead-lock bar adapted to engage andsubsequently be engaged by said snap-lock bolt, with distantly locatedcontrolling means having flexible connection with said door mechanisms,and a weight at the door adapted to draw back on the flexibleconnection, the operation of the weight being controlled by the deadlock bar; said distant means being moved away from and then immediatelyreturned to its normal position, thereby first pulling on the flexibleconnection, and then giving back its entire slack, the pull eflectingthe unlocking movements of the said parts at the door, and the slack, asdrawn back by the weight, permitting said parts to return toward theirlocked positions.

21. In a series of prison cells, the combination at each cell-dooropening of a slidable door, a locking bolt adapted to engage the door, abar adapted to dead-lock said bolt when it is in locked position, amovable master bar having a notch at each door, a connecting bolt on thedoor adapted to engage said notch of the master bar, and means forcontrolling the position of the connecting bolt, said means beingcontrolled by and moving in unison with the dead-lock bar, whereby whensaid bar is in dead-locking position the said connecting bolt is heldout of the plane of engagement with said notch of the master-bar.

22. In a series of prison cells opening upon a common corridor andhaving. slidable doors, the combination of longitudinally movable masterbar extending to all of the doors and at one end beyond the corridor, anotch in the master bar at each door with means for independentlyconnecting each or any door to said master bar, a gear rack on that endof the master bar extending beyond the corridor, a reciprocal gear wheelengaging said rack, a fixed g'ea-r rack also engaged by said wheel onits side opposite the master bar, with draft links connected: to theshaft journal" of the said gear wheel, and means for moving them in thesame direction as the master bar whereby the master bar is moved twiceasfast and twice as far as the movement of said gear wheel.

23. In a series of prison cells opening upon a common corridor andhaving slidable doors, the combination of a longitudinally movablemaster bar to which the doors may be connected having one end extendingbe yond the corridor, a geared rack on this end of the master bar, areciprocal gear wheel engaging said rack, a fixed gear rack also engagedby said wheel, a draft link connected to the shaft journal of the wheel,a crank arm to which said link is also connected, with means for turningsaid crank arm through a half revolution to aline it at the end of eachhalf throw with said link whereby the master bar is moved a distanceequal to twice the throw of the crank and it is dead locked againstmovement through any endwise force applied from the master bar whilesaid crank is on either of its dead centers.

24-. In a series of prison cells opening upon a common corridor and eachhaving a slidable door, the combination of a longitudinally movablemaster bar to which the doors may be connected, having one end extendingbeyond the corridor, a crank operating through link connection to movesaid master bar, said crank making a half revolution only and stoppingon its dead center relatively to said link connection, a concentric gearwheel attached to said crank, a vertically movable bar having a gearrack to engage said gear wheel, a second gear rack on the other end ofsaid bar, and a pinion engaged thereby, a lever connected with saidpinion and adapted to turn through a half revolution to full throw themaster bar.

25. In a series of prison cells opening upon a common corridor and eachhaving a slidable door, the combination of a longitudinally movablemaster bar to which the doors may be connected and which extend at oneend beyond the corridor, a crank having link connection with said masterbar. a concentric gear wheel connected to said crank, a verticallymovable rack bar engaging said gear wheel, a inion also engaged by saidrack bar, with a lever connected to said pinion and adapted to turn itin either direction to reciprocate the master bar, with fixed clamps toengage and hold said lever at the ends of its throw.

26. In a series of prison cells having door openings upon a commoncorridor and an ante-room at the end of the series of cells andpreferably inaccessible from said corridor, the combination of a boxcasing extending from said ante-room along the corridor above all thecell door openings and slotted at its bottom in front of each cell, alongitudinally movable master bar in said casing having a notch withinclined side approaches at each .cell, a door at each cell having a topplate extending through the slot and into said box casing, a rail trackin the casing and rollers, carried by the door plate, riding on saidrail, a connecting bolt vertically movable in guides on the door plate,a vertically adjustable lift rail supported on the box casing andadapted to slidably support the said connecting bolt, means forcontrolling said lift rail, and a suitable connection extending fromsuch means at each door through the box casing to controlling means inthe ante-room.

27. In a series of prison cells having door openings upon a commoncorridor'and an ante-room at the end of the corridor, preferablyinaccessible therefrom, the combination of a box casing extending fromsaid anteroom along the corridor above all cell door openings andslotted at its bottom in front of each cell, a longitudinally movablemaster bar in said casing having notches at each cell, a door at eachcell having a top plate extending through the slot and into the boxcasing, means on said plate for slida-bly supporting the door on a railin the casing, a movable bolt on said plate adapted to connect the doorto the master bar, and means for controlling said connecting bolt, anautomatic locking device adapted to engage the door when it is closedand a dead lock for such locking device, with means for retracting theautomatic locking device, for controlling said dead lock and forcontrolling said connecting bolt, a tension rod or wire connected tosaid means and extending therefrom through the box casing to the anteroom and connecting to individual controlling means in said ante-room.

28. In a series of prison cells opening upon a common corridor andhaving doors each provided with suitable locking and moving mechanismswhich are principally inclosed in a box casing extending along thecorridor above the door openings to an anteroom at the end of thecorridor, the combination of an endwise movable horizontal bar at eachcell adapted to control the several individual mechanisms of the doorreferred to, a connecting rod extending in said box casing from said barto operative and controlling mechanisms in said ante-room beyond the boxcasing, a rotatable spindle held against endwise movement and havingscrew grooves, a non-rotatable sleeve nut engaging the grooves of thespindle and adapted to move endwise thereon whereby said spindle may berotated in either direction in accordance with the movements of thesleeve nut, a pinion on said spindle, a gear rack on gagedand movedendwise thereby, with means for transmitting its movements to theconnection rod leading to the door mechanism as described.

29. In a series of prison cell-door locking cating said sleeve nuts.

30. In prison cell-door locking and operating devices, operable throughreciprocal bars immediately associated therewith and suitably connectedto distant individual operating and controlling means, the combinationin each of said last mentioned means, of a rotatable screw spindle heldagainst endwise movement, a pinion on the spindle, a horizontallyreciprocal rack bar engaged thereby, a non-rotatable sleeve nut engaging the screw spindle and movable endwise thereon, means exertinglifting pressure on said sleeve nut, and means whereby the sleeve nutmay be depressed to be immediately raised by said lifting means, wherebythe spindle is rotated first in one direction and then in the other,thereby moving said rack bar longitudinally forward and backward, whichmovements are transmitted to the reciprocal bars at the cell doors.

31. In a series of prison-cell doors having locking and operatingdevices, as described, immediately associated with them and operablethrough suitable connections by a series of distant individual means,the combination in each of said distant means of a vertical screwspindle, a pinion on said spindle, a horizontally reciprocal rack barengaged thereby, a non-rotatable sleeve nut engaging the screw spindleand movable endwise thereon, a bar extension of the sleeve nut passingthrough suitable guides, and a lever connected to said sleeve nut andadapted to longitudinally reciprocate the sleeve nut and its bar, with alock casing inclosing the series of said means and having slots in itsfront face through which said operating levers pass, and graduationmarks on its front face whereby the positions of said operating leversindicate the status of their respective locking mechanisms at the celldoors.

32. In a series of prison-cell doors having locking and operatingdevices, as described, immediately associated with them and oper ablethrough suitable connections by distant individual means, thecombination in each of said means of a vertical screw spindle, a pinionon said spindle and a horizontally reciprocal rack bar engaged thereby,a nonrotatable sleeve nut engaging the screw spindle and movable endwisethereon, a bar extension on the sleeve nut passing through suitableguides and having a longitudinal slot, a spring pressing to raise saidbar and sleeve nut, and a lever connected to the sleeve nut and adaptedto depress it against the spring pressure, said lever also passingthrough the slot in said bar, a lock casing inclosing said devices, withslots in its front face for the passage of said levers.

33. In a series of prison cell-door locking and operating mechanismscontrollable through individual longitudinally movable membersassociated therewith, in mechanisms adapted to move and control saidmembers, the combination of rotatable screw spindles held againstendwise movement, pinions on said spindles and gear racks engagedthereby, sleeve nuts engaging said screw spindles and endwise movablethereon, a plate adjacent to the sleeve nuts having guide slots parallelto the movement of the sleeve nuts and projections from said sleeve nutstaking into their respective slots in said plate to prevent the sleevenuts from turning when moving endwise to rotate the spindles, with meansfor reciprocating said sleeve nuts.

34. In prison cell-door locking and operating devices operable throughreciprocal bars immediately associated therewith and suitably connectedto distant individual operative and controlling means, the combinationin each of said last mentioned means of a rotatable screw spindle heldagainst endwise movement, a pinion on the spindle, a horizontallyreciprocal rack bar engaged thereby, a non-rotatable sleeve nut engagingthe screw spindle and movable endwise thereon, means exerting liftingpressure on said sleeve nut, means to check the rise of the sleeve nutat its normal position below its extreme rise, and means whereby thesleeve nut may be depressed below said nor mal position to beimmediately returned thereto by said lifting means, whereby said spindleis rotated first in one direction and then in the other thereby movingsaid rack bar longitudinally forward and back, which movements aretransmitted to the reciprocal bars at the cell doors.

35. In a series of prison-cell doors having locking and. operatingdevices as described immediately associated with them and operablethrough suitable connections by distant individual means, thecombination in each of said means of a vertical screw spindle, a pinionon the said spindle, a horizontally reciprocal rack bar engaged thereby,a non-rotatable sleeve nut engaging the screw spindle and movableendwise thereon, a bar extension of the sleeve nut passing throughsuitable guides, and a spring pressing to raise Said bar and sleeve nut,a spring pressed locking slide adapted to prevent the upward springmovement of the said

